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Man can change his pupil size on command

livescience.com

51–60 of 155 posts

Re: Man can change his pupil size on command

#52
"Once thought impossible," apparently, by people who have no exposure to the individual variability of humans, no faith in self-reported anecdata, or at least no desire to consider anything less philosophically perfect than spherical friction-less cows when contemplating biology.

Re: Man can change his pupil size on command

#53

When dental assisting, it has been challenging to discover how many people have no voluntary control over their own tongues.

MRI tech here: I’m surprised how many appear to have no control over their limbs. Please keep still.

Don't make me contort into an awkward position inside a screaming metal disk then :(

Re: Man can change his pupil size on command

#54

When dental assisting, it has been challenging to discover how many people have no voluntary control over their own tongues.

I have very little proprioceptive sense of my tongue, and when I'm at the dentist I have to consciously move it to know where it is. I basically pick a corner away from the dental instrument and touch the tip to that corner. After a minute or so I'll drift back to center and will hardly notice it.

I often ask the technician if my tongue is in the way, and they always say it's not, but I'm not sure I believe them. I sometimes have anxiety that if my tongue slips a little bit I'll get injured, and that sure doesn't help.

Physiologically, I would imagine that when the mouth is closed, the tactile pressure on the tongue is constant enough that your brain filters it out. When my mouth is open, the tactile pressure is gone, so there's even less sense of location. Without the muscle extension, it's just a blob of jello with no sensation. Hence why I place the tip at a specific corner.

Re: Man can change his pupil size on command

#55

When dental assisting, it has been challenging to discover how many people have no voluntary control over their own tongues.

MRI tech here: I’m surprised how many appear to have no control over their limbs. Please keep still.

On behalf of patients, we're sorry! The first time I had an MRI, my tech told me over the speaker that I was moving around too much. I was really surprised as I'd thought I was staying completely still!

I had another one more recently in which I apparently did much better. The trick for me seems to be to focus on my breathing and mental relaxation rather than trying to consciously "hold still."

Re: Man can change his pupil size on command

#56

Earlier quoted context omitted.

> It was previously known that some people can change their pupil size at will, but by using indirect methods. > For example, researchers already knew that just thinking about the sun could constrict the pupils and that thinking of a dark room or mentally calculating something could dilate them, […] Apparently, it is about changing the pupil’s size without any physical or mental stimulus.

How would you be able to tell if they were using 'mental stimulus' or not?

It's in the abstract of the paper. They used fMRI

Re: Man can change his pupil size on command

#57
post #4

A quick search online brings up multiple articles dating back a few years with examples of the same thing. It's not "an impossible feat". https://www.bbc.com/future/article/20160229-the-sea-nomad-ch...

Yeah. I've been able to do this for years. Not immediately, but with some concentration and focus when standing in front of a mirror. Works probably 75-80% of the time. So, "impossible feat"... how would they even think that?

If it takes time and is not wholly reliable, it sounds like you might be using one of the "indirect methods" they mentioned in the article.

Re: Man can change his pupil size on command

#58
post #4

A quick search online brings up multiple articles dating back a few years with examples of the same thing. It's not "an impossible feat". https://www.bbc.com/future/article/20160229-the-sea-nomad-ch...

This was the first thing that came to mind. They show the children controlling their pupils. https://youtu.be/YIKm3Pq9U8M

Re: Man can change his pupil size on command

#59
post #17
post #3

I didn't think this was special? I've done this in the mirrior? Not fast or anything, but it is "on demand".

Came here to say this as well, I can change mine without moving when looking in a mirror - to me it "feels" like I'm focusing my eyes on something that isn't there.

Same here. I used this to impress my friends in primary school. I couldn't find another use for it though.
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